The present invention relates to a device for processing process or industrial wastewater developing in manufacturing, for example.
In a variety of manufacturing, process wastewater develops, in which oils, solvents, or other processing residue is included in the water or another liquid. It is necessary to clean such processing wastewaters for either recycling these process wastewaters for the processing cycles or allowing their discharge to the sewer system. Here, particularly for the discharge into the sewer system, sometimes statutory limits have to be observed as well.
In order to increase the purity of the above-mentioned distillation methods several cleaning steps can be performed consecutively, however this considerably increases the expense for equipment and the space needed. In general it can be said that the expenses connected to cleaning process wastewater increases disproportionably the higher the targeted purity.
The present invention relates to a one-step distillation process which is provided with a closed energy circuit for reducing the application of energy. Processing devices having an evaporator are already known which are formed by a tube bundle heat exchanger. Due to the fact that each distillate continues to show a content of volatile oils to a greater or lesser extent, with here oil being mentioned only as an example for other volatile polar and non-polar hydrocarbons, the processing devices of prior art comprise coalescing bodies provided perhaps with rock wool or interlaced stainless steel to reduce, for example, the portion of oil in the distillate in wastewater purification. However, such coalescence chambers of prior art cannot prevent the oil-water mixture from containing oil to a greater or lesser extent. Although the portion of free oil in the distillate floats and can be skimmed off, the remaining distillate may still represent a comparatively stable oil-water emulsion.